“Big data” is a term for data sets that are so large or complex that traditional data processing applications are inadequate. Challenges include analysis, capture, data curation, search, sharing, storage, transfer, visualization, querying and information privacy. The term “big data” often refers simply to the use of predictive analytics or certain other advanced methods to extract value from data, and seldom to a particular size of a data set. Accuracy in big data may lead to more confident decision making and better decisions can result in greater operational efficiency, cost reduction and reduced risk.
A spheroid, or ellipsoid of revolution, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters. If the ellipse is rotated about the major axis of the ellipse, the result is a prolate (elongated) spheroid, shaped like an American football or rugby ball. If the ellipse is rotated about a minor axis of the ellipse, the result is an oblate (flattened) spheroid, shaped like a lentil. If the generating ellipse is a circle, the result is a sphere. A spheroid has circular symmetry.